Question

Arrange static friction, rolling friction and sliding friction in order of increasing order.

Answer 1

Static friction:

1. When an object is in a rest position, then the body exerts a force that keeps the body continuously at rest. This force is known as static friction.
2. Static friction has maximum resistance in comparison to other types of friction forces.

Rolling Friction:

1. When an object is in motion on a floor, the body keeps changing points of contact with the floor's surface. This force is known as rolling friction.
2. Rolling friction has minimum resistance in comparison to other types of friction forces.
3. For example, the wheels of the car move on the road, it consists of rolling force.
4. When an object is in motion on a floor, the body keeps changing points of contact with the floor's surface. This force is known as rolling friction.
5. Rolling friction has minimum resistance in comparison to other types of friction forces.
6. For example, the wheels of the car move on the road, it consists of rolling force.

Sliding Friction:

1. When an object is sliding on another surface. This force is known as sliding friction.
2. Sometimes it is also called kinetic friction.

Explanation:

1. For example, a book is placed on the table, it consists of static friction force. Similarly, when the box starts sliding, the contact points on its surface do not get enough time to lock into the contact points on the floor. So the sliding friction is smaller than the static friction.
2. If a wheel rolls without slipping, we need not apply any force against the locking between the surfaces, and thus less force is required as compared to sliding friction. So rolling friction is less than the sliding friction.
3. So, the correct increasing order of frictional forces are

Rolling friction < Sliding friction < Static friction.